Flavonoids, chemistry flavonols

A detailed study of the flavonoid chemistry of the island endemics, the closely related G. tinctoria, and live additional species from the mainland provided additional evidence pointing toward G. tinctoria as the ancestral species (Pacheco et al., 1993). The flavonoid profiles of all species consisted of flavonol glycosides as major components with an unidentified flavone glycoside and several unidentified phenolic compounds (presumably not flavonoids). The pattern of distribution of the flavonol glycosides and unidentified flavones within the set of nine species proved to be extremely informative. (The phenols were ubiquitous and are not considered further.) Kaempferol glycosides were seen in neither the island species nor G. tinctoria, but were present, in several combinations, in the rest of the mainland taxa. The isorhamnetin glycosides showed the reverse pattern, with one exception the island endemics and G. tinctoria exhibited these compounds, whereas four of the other mainland species did not. The sole exception is G. boliviari, which exhibited one of the isorhamnetin derivatives. 

Valant-Vetschera KM and Wallenweber E. 2006. Flavones and flavonols. In Anderson OM and Markham KR, editors. Flavonoids Chemistry, Biochemistry and Applications. Boca Raton, FL CRC Press/Taylor Francis Group, pp. 618-748. 

Fig 2.1 Early contributions to the flavonoid chemistry of the Leguminosae. The isoflavone glucoside, ononin (1), first obtained from the roots of Ononis spinosa (spiny restharrow) by Reinsch in 1842. Robinin (2), a flavonol 3,7-O-glycoside from the flowers of Robinia pseudoacacia (black locust tree), first mentioned in the literature by Zwenger and Dronke in 1861. 

Wilhams, C.A. (2006). Flavone and flavonol O-glycosides. In Flavonoids Chemistry, Biochemistry and Applications (eds 0.M. Andersen K.R. Markham), pp. 749-856. CRC Press, Boca Raton. 

Hattori, S., Glycosides of flavones and flavonols, in The Chemistry of Flavonoid Compounds, Geissman, T.A., Ed., Pergamon Press, Oxford, 1962, chapter 11. 

The chemistry and biology of flavonoids is complex, and both beneficial and detrimental effects of flavonoids in mamnals have been predicted. Some of the reported cellular and biochemical effects of flavones and flavonols are summarized in Table 4. Many of the reported cellular effects of flavonoids could indirectly influence the biochemical processes related to ONA replication and/or tumor progression. 

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